Tracheal tube with disposable cannula

Abstract

A tracheal tube having straight inner and outer end portions integrally connected by a curved central portion contains a cannula that can be removed from one end. The cannula is a normally straight one-piece flexible tube of plastic circumferentially corrugated from approximately its inner end outwardly to a point at least as far as the outer end of the curved central portion of the tracheal tube. The corrugated wall of the cannula stiffens the part of the cannula that extends through the curved central portion of the tracheal tube to prevent it from collapsing when the cannula is inserted in the tracheal tube.

We claim: 
     
       1. The combination of a rigid tracheal tube having substantially straight inner and outer end portions integrally connected by a curved central portion that has a radius of curvature between about 5/8 inch and 1 1/4 inch long, and a disposable cannula fitting in said tube and extending from end to end thereof, said end portions of the tracheal tube being disposed at an angle to each other of between about 90° and 100°, and said cannula being a normally straight one-piece flexible tube formed of a plastic and having a solid wall less than 1 mm thick circumferentially corrugated from approximately its inner end outwardly to a point at least as far as the outer end of said curved central portion of the tracheal tube, said corrugated wall stiffening radially the length of cannula extending through said curved central portion of the tracheal tube and maintaining said length of cannula uncollapsed, the cannula being removable from the tracheal tube by pulling the outer end of the cannula. 
     
     
       2. The combination recited in claim 1, in which the tracheal tube from said outer end portion to the inner end of the tube has a substantially uniform diameter of between about 5 and 10 mm, and the corrugated length of the cannula is of substantially uniform size throughout its length to engage the inner surface of the tracheal tube. 
     
     
       3. An endotracheal device comprising a rigid tracheal tube having substantially straight inner and outer end portions integrally connected by a curved central portion that has a radius of curvature between about 5/8 inch and 1 1/4 inch long, said end portions of the tracheal tube being disposed at an angle to each other of between about 90° and 100°, the portions of said tube from its inner end to said outer end portion having a substantially uniform inner diameter of between about 5mm and 10mm, the inner diameter of said outer end portion being enlarged to provide a socket, and a disposable cannula fitting in said tube and extending from end to end thereof, said cannula being a normally straight one-piece flexible tube formed of a plastic and having a solid wall less than 1mm thick circumferentially corrugated from approximately its inner end outwardly to a point at least as far as the outer end of said curved central portion of the tracheal tube, the corrugated length of the cannula having a substantially uniform size throughout to engage the surrounding inner surface of the tracheal tube, said corrugated wall stiffening radially the length of cannula extending through said curved central portion of the tracheal tube and maintaining said length of cannula uncollapsed, and the outer end portion of the cannula being enlarged and smooth and uncorrugated and fitting in said socket, and the cannula being removable from the tracheal tube by pulling the outer end of the cannula. 
     
     
       4. The combination recited in claim 3, in which the tracheal tube from said socket to its inner end has a substantially uniform inside diameter, and the corrugated length of the cannula is of substantially uniform size throughout its length to engage the inner surface of the tracheal tube. 
     
     
       5. The combination recited in claim 4, in which the wall thickness of said cannula is less than 1/2 mm.